前缀pre-与前面学过的post-是一对相反的词缀，它来自拉丁介副词prae ,原意为before, beforehand或in front,即表示时间或空间上的“前”。pre-原是个有副词含义的原生词，出现于拉丁语源的原生词中。但自15世纪以来，它成为一个活性的派生词缀，能与许多单词缀合，起介词性或修辞性的作用。当介词性的pre-与名词缀合时，可能改变词基单词的词性。当派生前缀pre-出现在以e开头的单词或大写字母时，要加连字符。此外，应注意原生前缀pre-中的e读短音/i/，而派生前缀pre- 中的e念长音/i:/。

为便于埋解，这里先介绍派生前缀pre-与单词缀合的例子。

prehistory [ pre- = before 前；history n. 历史→] n. history before recorded history (历史记载前的)史前史 / A team of archaeologists has discovered traces of a lost people of prehistory. 一队考古学者已经发现了一个不为人所知的史前民族的遗迹。

prehistoric a. (有记载的）历史以前的；史前的

pre-election [pre- = before 在…前；election n. 选举→]a. happened or said before election选举前发生的；选举前说的/ He has completely forgotten his pre-election promises. 他已将选举前的许诺忘得一干二净。

premature [pre- = beforehand, early 事先，过早；mature a. 成熟的→]a . mature too early; before the proper time 早熟的；过早的 / A premature baby is one born more than two weeks early. 早产婴儿指提早两周以上出生的小孩。

prematurity n. 早熟，不成熟；过早，不到时

prejudge [ pre- = beforehand 事先；judge v. 判断→]v. judge beforehand, especially without knowing all the facts 过早判断 / The jury should keep an open mind during the trial and not prejudge the case. 陪审团在审理过程中应虚怀若谷，不可过早断案。

prejudgement n. 过早判断；不审而判